Alpha Fan runs at max. speed Fault Code
Also written as FANRUNSATMAXSPEED — same fault.
The Alpha Fan runs at max. speed fault code means: your boiler's fan is running continuously at full speed, which indicates the system has detected a safety concern and is trying to clear the air inside the unit.. It appears on 2 Alpha models in our database.
Technical description: Follow section 'D' fault finding
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Alpha models that show the Fan runs at max. speed fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Alpha Fan runs at max. speed fault code information on this page is sourced and cross-checked against the official Alpha service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026